Electronic documents are used for a wide variety of applications. In many cases, electronic documents incorporate content that may be erroneous. Examples of such potentially erroneous content include content received from an external source, such as a vendor, partner or user. Such content can compromise the integrity of a document with which it is associated. Many forms of such compromises are possible. Examples include content injection such as cross-site scripting, SQL injection and HTTP response splitting. Some such compromises include erroneously ending a document, an element of a document, or metadata associated with a document. Compromises to the integrity of documents have been used for malicious and/or fraudulent purposes.
The absence of a mechanism for protecting the integrity of documents and/or their associated elements and/or metadata leaves the door open for many such compromises. Accordingly, it would be useful to be able to protect the integrity of electronic documents.